- problematic boyfriend. D:?

Alright, here's the deal. I need some boyfriend advice. D: So, today in school, they were selling chocolate bars for a dollar. I asked my boyfriend if he could lend me a dollar to get me one, and he said that he didn't want to spend his money because he needed to get cigarettes. I wasn't mad about the situation, at all. I brushed it off and moved along with my day. Whenever we got into Accounting cl, I asked my ex boyfriend Nick for a dollar, being he had a dollar in his hand at the moment. And he gave me the dollar and I went to go get one whenever my boyfriend asked where I was going and I answered: Nick gave me a dollar for the chocolate bar since you won't get me one. I didn't say it rudely, at least I didn't think so? And after that, he totally freaked out on me. He said that if he wasn't good enough for me, I should run along with my ex, whenever I clearly didn't say that. It felt like he put a thousand words into my mouth. He did apologize later on in the day, but, the way he yelled at me, and the things he said, it's just still replaying? Any advice?